2-halo-4-alkyl-phenyl-phosphoramidates

ABSTRACT

COMPOUNDS OF THE FORMULA   1-(R-C(-R1)(-R2)-),3-((R-)2-N-P(=X)(-R3)-O-),4-(HAL-)   BENZENE   IN WHICH R, R1 AND R2 REPRESENT ALIPHATIC RESIDUES, R3 REPRESENTS AN ALKYL GROUP WHICH MAY BE LINKED WITH THE PHOSPHORUS ATOM THROUGH OXYGEN OR SULFUR, X IS O OR S AND HAL REPRESENTS A HALOGEN ATOM. THE PHOSPHORIC ACID ESTER AMIDES ARE EFFECTIVE AS SELECTIVE HERBICIDES AS WELL AS PLANT-GROWTH REGUALTORS IN USEFUL PLANT CROPS.

United States Patent v ()fticev 3,044,600 Patented Feb. 22, 1972 3,644,600 2-HALO-4-ALKYL-PHENYL-PHOSPHORAMIDATES Ernst Beriger, Neuallschwil, Switzerland, assignor to Ciba Limited, Basel, Switzerland No Drawing. Filed Feb. 26, 1969, Ser. No. 802,627 Claims priority, application Switzerland, Mar. 1, 1968,

83/68 Int. Cl. A01n 9/36; C0713 9/12, 9/22 US. Cl. 260-959 Claims ABSTRACT OF THE DISCLOSURE Compounds of the formula in which R, R and R represent aliphatic residues, R represents an alkyl group which may be linked with the phosphorus atom through oxygen or sulfur,'X is O or S and Hal represents a halogen atom. The phosphoric acid ester amides are effective as selective herbicides as well as plant-growth regulators in useful plant crops.

in which the substituents R, independently of one another, represent hydrogen, an alkyl group having 1 to 4 carbon atoms or possibly R R represents an alkyl group having 1 to 4 carbon atoms, R represents an alkyl or alkenyl group having 1 to 6 carbon atoms, R represents an alkyl group having 1 to 5 carbon atoms which may be linked with the phosphorus atom through oxygen or sulphur, X represents an oxygen or a sulphur atom and Hal represents a halogene atom, having a pronounced selective activity against monocotyledenous weeds for example Panicum, Poa, Digitaria or Alopecurus, While leaving important (including monocotyledenous) useful cultures for example grain crops, rice, maize, turnips, flax, soybeans, cabbages and others, and in the case of some cultures, they even display a useful growth-regulating effect. Compounds that are especially active, are those in which the substituents R, independently of one another, represent hydrogen or an alkyl group having 1 to 4 carbon atoms.

Thisconsiderable breadth of activity was unexpected, and has not hitherto been known to a similar extent with phosphorus compounds.

The weeds can be combated in the plant cultures both by the pre-emergent and the postemergent treatment, though the pre-emergent treatment is preferred.

In addition, the compounds of the Formula I display a good fungicidal activity when applied in small quantities.

Compounds of the formula have a mainly selective herbicidal activity; in this formula the substituents R, independently of one another, represent hydrogen or an alkyl group having 1 to 4 carbon atoms, R represents an alkyl group having 1 to 5 carbon atoms, which may be linked with the phosphorus atom through oxygen or sulphur, X represents an oxygen or a sulphur atom, and Hal is a halogen atom.

Among the said compounds, there are especially suitable for this purpose those which correspond to the formula in which the generally indicated substituents R R Hal and X have the above meanings.

A group of compounds of importance to the selective control of plants comprises the compounds of the formula' in which R represents a hydrogen atom or the methyl group, R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R';, represents an alkyl group and Hal represents a halogen atom. The compounds of the general Formula I are new. They can he -manufactured by various methods:

(a) A suitable phenol is reacted with phosphorus trichloride and sulphur, and the resulting rial I 9 Hal \H- Hal can be used in the further reaction.

(b) Alternatively, in a dilferent sequence of operations O-alkyl-dichlorophosphate or -dichlorothiophosphate, or

alkyldichloro-dithiophosphate may be used as starting material and reacted with the corresponding phenol and then with the desired alkylamine.

Alternatively, the parent phosphorus component (PCl PBr or PXCl may be reacted first with the alkylamine and the resulting with the lower alkanol or mercaptan and the phenol, in either order of sequence.

As mild dehydrohalogenating agents, which may advantageously be added, there may be used: anhydrous hydrogencarbonates or carbonates, also tertiary amines for example triethylamine, pyridine, picoline, lutidine, quinaldine, diethylaniline and dimethylaniline.

In general, the new compounds of the general Formula I are used alone or in conjunction with additives in the form of herbicidal preparations.

The present invention also provides a selective herbicidal preparation which comprises a compound of the general Formula I given above together with a suitable carrier.

As additives for use in plant control, the known herbicides whose activity supplements that of the compounds of this invention may be employed, for example 2-methyl- 4-chlorophenoxyacetic acid, 2-methyl-4-chlorophenoxybutyric acid and/or ot-[Z-methyl-4-chlorophenoxy] -propionic acid, and growth hormones.

The preparations may also contain one or more of the following: a vehicle, a solvent, a diluent, a dispersant, an emulsifier, a thickener, an adhesive and/or a fertilizer and, if desired, further pesticidal agents from the same or other spheres of application.

The form in which these preparations are applied depends entirely on their future use. They can be applied in a wide variety of forms, for example in the form of emulsions, dusting powders, dispersions or granulates.

Ready spray solutions of the compounds of the general Formula I can be prepared, for example, with petroleum fractions of a high to medium boiling range, for example diesel oil or kerosene, coal tar oil and oils of vegetable or animal origin, also hydrocarbons for example alkylated naphthalenes, tetrahydronaphthalene, if desired with the use of xylene mixtures, cyclohexanols, ketones or chlorinated hydrocarbons for example trichlorethane or tetrachlorethane, trichlorethylene, or trior tetrachlorobenzenes. It is advantageous to use organic solvents having boiling point above 100 C.

Aqueous forms of application are advantageously prepared from emulsion concentrates, pastes or wettable spray powders by the addition of water thereto. Suitable emulsifiers or dispersants are nonionic products, for example condensation products of aliphatic alcohols, amines or carboxylic acids with a long-chain hydrocarbon residue having about to carbon atoms, with ethylene oxide, for example the condensation product of octadecyl alcohol with to mols of ethylene oxide, or of commercial oleylamine with 15 mols of ethylene oxide, or of dodecylmercaptan with 12 mols of ethylene oxide. As anionic emulsifiers that can be used, there may be mentioned the sodium salt of dodecyl alcohol-sulphuric acid ester, the sodium salt of dodecylbenzenesulphonic acid, the potassium or triethanolamine salt of oleic or abietic acid or of mixtures of these acids, or the sodium salt of a petroleumsulphonic acid. Suitable cationic dispersants are quaternary ammonium compounds, for example cetyl pyridinium bromide or dihydroxyethyl benzyl dodecyl ammonium chloride.

As solid vehicles used in the manufacture of dusting and casting preparations there may be used: talcum, kaolin, bentonite, calcium carbonate, or coal, cork meal, wood meal or other materials of vegetable origin. It is also very advantageous to manufacture the preparations in granular form, especially for treating rice cultures in water. The different forms of application may contain the usual additives that improve the distribution, adhesion, stability to rain or the penetration; such substances are fatty acids, resins, casein or alginates.

The following examples illustrate the invention, the parts being by weight, unless otherwise indicated.

EXAMPLE 1 36.5 parts of 2-bromo 5 tertiary butylphenylthiodichlorophosphate [boiling at l18l20 C. under 0.2 mm. Hg; prepared by reacting 2-bromo-S-tertiary-butylphenol in the usual manner with phosphorus trichloride and sulphur] in 50 parts by volume of methylene chloride and 6.4 parts of methanol are boiled under reflux for 16 hours. The readily volatile phase is evaporated under vacuum at 50 C. bath temperature, to leave 35 parts of O-methyl-2- bromo-5-tertiary butylphenylthiochlorophosphate.

34 parts of this compound are dissolved in 150 parts by volume of methylenechloride and 11.2 parts of isopropylamine are added drop by drop during 30 minutes at 15- 25 C. The batch is stirred overnight at room temperature, parts of water are added and the organic layer is separated, washed, washed successively with 30 parts of water, 2X20 parts of dilute sodium hydroxide solution and dried over sodium sulphate. After having removed the solvents under vacuum at 50 C. bath temperature there are obtained 33 parts of the compound of the formula 1130 11 iso) Hal are obtained:

Refractive index Compound N o.

Methyl .41 do Methyl nu Ethyl n .5425 -.do n-Propyl n =L 5332 do Methyl nn =1.5554 --d0 Ethyl nn =1.5552 do n-Propyl nD =L5440 d0 Isopropyl n =l.5443

as Well as the following compounds:

Refractive Compound No. Formula index 18 (CH3)3C n =1r5368.

. fi/OGHs v OP C2H5 N Br 19 (CH3)3O 77.1 =l.5476

| S OCHs Il/ O-P N(CHr-CH=CH2)2 Br 20 CH3CHCH3 7LD25=1.5458

fi/OCHs OP NHC H1(iso) Br 21 (CHmO 'nn =1.5618

lSl OOH; -OP\ /CHa I N Br CHQ-CZCHZ h 22 (CHmC nD =L5470 l S CzHi NHC Hfliso) Br EXAMPLE 2 C(ca 5 3 2 sc n O-P [Compound No. 23].

Examples of formulations Dusting agent.--Equal parts of an active substance according to this invention and of precipitated silica are finely ground together. From this mixture, dusting preparations containing preferably 1 to 6% of active substance, can be manufactured by incorporation of kaolin or talcum.

Spray powder.For manufacturing a spray powder, for example, the fOllOWing ingredients are mixed and finely ground together:

50 parts of active substance of this invention 20 parts of Hisil (highly adsorptive silica) 25 parts of bolus alba (kaolin) 3.5 parts of an adduct of para-tertiary octylphenol With ethylene oxide 1.5 parts of sodium1-benzyl-2-stearylbenzimidazole-6.3'-

disulphonate.

Emulsion concentrate.Readily soluble active substances can also be formulated as emulsion concentrates in the following manner:

20 parts of active substance, parts of xylene and 10 parts of a mixture of the reaction product of an alkylphenol and ethylene oxide with calcium dodecylbenzenesulphonate are mixed together. When this mixture is diluted with Water to the desired concentration, an emulsion ready for spraying is obtained.

Granulate.7.5 grams of one of the active substances of Formula I are dissolved in cc. of acetone and the resulting acetonic solution is poured over 92 g. of granulated attapulgite (mesh size: 24/48:apertures/inoh). The whole is thoroughly mixed and the solvent extracted in a rotary evaporator, to furnish a granulate containing 7.5% of active substance.

EXAMPLE 3 In the preemergent treatment, the new active substances of the Formula I displayed an excellent activity against grass-like weeds, while leaving cultures of grain crops, rice and maize as well as of dicotyledenous plants unaffected.

The treatment was carried out with 5 and respectively 2.5 kg. of active substance per hectare on the day after seeding. Evaluation Was carried out 20 days later. The

resulting values are shown in the following Table 1, in which TABLE 1 kg active 2.5 kg active substance substance per hectare per hectare Compound 1 2 3 17 1 2 3 4 17 1 1 1 1 1 1 1 l 1 1 1 l 1 l l 1 l l l l l l l l l 1 l 1 8 9 9 7 8 l l 1 l 1 1 l l 1 l 1 l l l 1 -1" 1 1 1 1 l l 1 l 1 1 l l 1 EXAMPLE 4 Experiments in rice cultures Earth mixed with seeds of the Weed Panicum crus galli was introduced into vessels of asbestos cement (60 x 60 x 40 cm.) are covered with a 2 cm.-layer of water. The pre-swelled rice seed material, in one case of the Caloro type and in the other of the Hatsunisiki type, in admixture with the abovementioned granulate of one of the active substances was sprinkled into the water. The amount of active substance applied ranged from 1 to 6 kg. per hectare.

14 days after the application, the values shown in the following Table 2 were recorded (evaluation as in Example 3).

These experiments revealed the high specific selectivity of the compounds of this invention, which is observed even with as large amounts as 4 and 6 kg. respectively of the active substance per hectare. Thus, there is no damage to the rice plants, even if too much of the majority of the substances mentioned is accidentally applied locally.

TABLE 2 Kg. active Type of rice substance Compound No. pcrhectare Caloro Hatsunisiki Echinochloa comm-5cmthceeomhwcozcmcooowwcocucoc 8 EXAMPLE 5 Growth regulation The compounds of the general Formula I are capable of 5 regulating plant growth, and with various plants they produce stunted growth by inhibiting the growth in height and the internodal growth respectively. The plants thus changed do not turn yellow, do not sutfer any other damage and remain photosynthetically active. As a result of the treatment with the above-mentioned compounds, it is often observed that the leaves are darker green in colour. The said compounds, or preparations containing them, also have further growth regulating properties; among others, they cause increased formation of lateral shoots with various plants.'

The following 10 plants were sown and 10 days after emergence were sprayed with 2.5 kg. of active substance per hectare; Beta, Calendula chrysantha, Chrysanthemum segetum, Lin um usitatissimum, Brassica rapa, Ipomoea purpurea, Gossypiumhirsutum, Soja max., Galium aparine, and Stellaria media.

Evaluation was carried out after days. The average growth inhibition evaluated for this representative selection of plants, for the individual active substance accordin g to this invention was:

Compound No. Scale No. Compound No. Scale No.

Compound No. Lin. Goss. Compound No. Lin. Goss.

(C) Various species of chrysanthemum plants, were seeded, and 7 weeks later their leaves were sprayed with a solution of 1000 parts per million of the active substance No. 3. When these plants blossomed out 7 weeks later, the height of their growth was distinctly reduced in comparison with corresponding untreated chrysanthemum plants. The following heights of growth were recorded.

Average height of the main shoots in percent (length of main shoots of corresponding, untreated plants: 100%) Percent Chrysanthemumsegetum 41 Chrysanthemum parthen'ium 47 Chrysanthemum coronarium 71 Chrysanthemum carinatum 79 Chrysanthemum indicum 58 No phytotoxic properties were observed in any experiment, that is to say that all plants had a healthy appearance, dark green leaves and a good flower formation.

(D) Wheat seeds were caused to germinate in distilled water for about 42 hours in the dark. The wheat seedlings, which had a length from 1 to 1.5 cm., were then trans- 5 ferred to culture vessels filled with active substance solution and, respectively, distilled water (=controls) and exposed to light. The active solution contained 100 parts per million of the active substance in the formulated preparation No. 3 in distilled water.

After 4 days, the solution of the active substance was replaced by a nutrient solution containing the same quantity of active substance (100 parts per million of active substance No. 3), while in the control experiments the distilled Water was replaced correspondingly by a nutrient solution which did not contain the active substance.

Measuring the height of growth of the wheat plants was carried out 10 days later. It was found that in the case of the plants treated with the active substance, the height of the second stalk internode was reduced on an average by 33.1% in comparison with the controls. The height of the stalk from its base to the second ligula in the case of the plants treated with the active substance was on an average reduced by 36.3% in comparison with the controls.

I claim:

1. Compounds of the formula N Hal in which the substituents R, independently of one another, represent a hydrogen atom, allyl, chloroallyl or R R represents an alkyl group having 1 to 4 carbon atoms, R represents an alkyl group having 1 to 6 carbon atoms, allyl or chloroallyl, R represents an alkyl group having 1 to 5 carbon atoms which may be linked with the phosphorus atom through oxygen or sulphur, X represents a sulphur atom and Hal is a halogen atom. 2. Compounds as claimed in claim 1 of the formula in which the substituents R, independently of one another, represent a hydrogen atom or R R represents an alkyl group having 1 to 4 carbon atoms, R represents an alkyl group having 1 to 6 carbon atoms, R represents an alkyl group having 1 to 5 carbon atoms which may be linked with the phosphorus atom through oxygen or sulphur, X represents a sulphur atom and Hal is a halogen atom.

3. Compounds as claimed in claim 1 of the formula in which the substituents R, independently of one another, represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R represents an alkyl group having 1 to 5 carbon atoms which may be linked with the phosphorus atom through oxygen or sulphur, X rep- 5 resents a sulphur atom and Hal is a halogen atom.

4. Compounds as claimed in claim 1 of the formula in which R, R Hal and X have the meanings given in claim 3.

5. Compounds as claimed in claim 1 of the formula Hal 1 Hal Mi-R in which R represents a methyl, ethyl, n-propyl or isopropyl group and Hal represents a chlorine, bromine or iodine atom.

7. The compound as claimed in claim 1 of the formula (cu c p S 3 3 oc a o-r Br Nil-(1 H 8. The compound as claimed in claim 1 of the formula CH CHCH 9. The compound as claimed in claim 1 of the formula c1 mica 10. The compound as claimed in claim 1 of the formula 00a 1' 3 G Br \NH-CH3 References Cited UNITED STATES PATENTS 3/1960 Wasco et al 260-959 X CHARLES B. PARKER, Primary Examiner A. H. SU'ITO, Assistant Examiner US. Cl. X.R. 

